#!/bin/sh
# SPDX-License-Identifier: GPL-3.0-only
#
# This file is part of the distrobox project:
#    https://github.com/89luca89/distrobox
#
# Copyright (C) 2021 distrobox contributors
#
# distrobox is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 3
# as published by the Free Software Foundation.
#
# distrobox is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with distrobox; if not, see <http://www.gnu.org/licenses/>.

# POSIX
# Optional env variables:
#	DBX_CONTAINER_MANAGER
#	DBX_VERBOSE

# Despite of running this script via SUDO/DOAS being not supported (the
# script itself will call the appropriate tool when necessary), we still want
# to allow people to run it as root, logged in in a shell, and create rootful
# containers.
#
# SUDO_USER is a variable set by SUDO and can be used to check whether the script was called by it. Same thing for DOAS_USER, set by DOAS.
if {
	[ -n "${SUDO_USER}" ] || [ -n "${DOAS_USER}" ]
} && [ "$(id -ru)" -eq 0 ]; then
	printf >&2 "Running %s via SUDO/DOAS is not supported. Instead, please try running:\n" "$(basename "${0}")"
	printf >&2 "  %s --root %s\n" "$(basename "${0}")" "$*"
	exit 1
fi

# Ensure we have our env variables correctly set
[ -z "${USER}" ] && USER="$(id -run)"
[ -z "${HOME}" ] && HOME="$(getent passwd "${USER}" | cut -d':' -f6)"
[ -z "${SHELL}" ] && SHELL="$(getent passwd "${USER}" | cut -d':' -f7)"

# If the user runs this script as root in a login shell, set rootful=1.
# There's no need for them to pass the --root flag option in such cases.
[ "$(id -ru)" -eq 0 ] && rootful=1 || rootful=0
extra_flags=""
all=0
container_manager="autodetect"
container_name_default="my-distrobox"
delete=0
icon="auto"
icon_default="${XDG_DATA_HOME:-${HOME}/.local/share}/icons/terminal-distrobox-icon.svg"
verbose=0
online=0
version="1.8.0"

# Source configuration files, this is done in an hierarchy so local files have
# priority over system defaults
# leave priority to environment variables.
#
# On NixOS, for the distrobox derivation to pick up a static config file shipped
# by the package maintainer the path must be relative to the script itself.
self_dir="$(dirname "$(realpath "$0")")"
nix_config_file="${self_dir}/../share/distrobox/distrobox.conf"

config_files="
	${nix_config_file}
	/usr/share/distrobox/distrobox.conf
	/usr/share/defaults/distrobox/distrobox.conf
	/usr/etc/distrobox/distrobox.conf
	/usr/local/share/distrobox/distrobox.conf
	/etc/distrobox/distrobox.conf
	${XDG_CONFIG_HOME:-"${HOME}/.config"}/distrobox/distrobox.conf
	${HOME}/.distroboxrc
"
for config_file in ${config_files}; do
	# Shellcheck will give error for sourcing a variable file as it cannot follow
	# it. We don't care so let's disable this linting for now.
	# shellcheck disable=SC1090
	[ -e "${config_file}" ] && . "$(realpath "${config_file}")"
done

[ -n "${DBX_CONTAINER_MANAGER}" ] && container_manager="${DBX_CONTAINER_MANAGER}"
[ -n "${DBX_VERBOSE}" ] && verbose="${DBX_VERBOSE}"

# Fixup variable=[true|false], in case we find it in the config file(s)
[ "${verbose}" = "true" ] && verbose=1
[ "${verbose}" = "false" ] && verbose=0

# show_help will print usage to stdout.
# Arguments:
#   None
# Expected global variables:
#   version: distrobox version
# Expected env variables:
#   None
# Outputs:
#   print usage with examples.
show_help()
{
	cat << EOF
distrobox version: ${version}

Usage:

	distrobox-generate-entry container-name [--delete] [--icon [auto,/path/to/icon]]

Options:

	--help/-h:		show this message
	--all/-a:		perform for all distroboxes
	--delete/-d:		delete the entry
	--icon/-i:		specify a custom icon [/path/to/icon] (default auto)
	--root/-r:		perform on rootful distroboxes
	--verbose/-v:		show more verbosity
	--version/-V:		show version
EOF
}

# Parse arguments
while :; do
	case $1 in
		-h | --help)
			# Call a "show_help" function to display a synopsis, then exit.
			show_help
			exit 0
			;;
		-v | --verbose)
			verbose=1
			shift
			;;
		-V | --version)
			printf "distrobox: %s\n" "${version}"
			exit 0
			;;
		-d | --delete)
			delete=1
			shift
			;;
		-a | --all)
			all=1
			shift
			;;
		-i | --icon)
			if [ -n "$2" ]; then
				icon="$2"
				shift
				shift
			fi
			;;
		-r | --root)
			shift
			rootful=1
			;;
		--) # End of all options.
			shift
			break
			;;
		-*) # Invalid options.
			printf >&2 "ERROR: Invalid flag '%s'\n\n" "$1"
			show_help
			exit 1
			;;
		*) # Default case: If no more options then break out of the loop.
			# If we have a flagless option and container_name is not specified
			# then let's accept argument as container_name
			if [ -n "$1" ]; then
				container_name="$1"
				shift
			else
				break
			fi
			;;
	esac
done

set -o errexit
set -o nounset
# set verbosity
if [ "${verbose}" -ne 0 ]; then
	set -o xtrace
fi

if [ -z "${container_name:-}" ]; then
	container_name="${container_name_default}"
fi

if [ "${all}" -ne 0 ]; then
	container_names="$(distrobox list --no-color | tail -n +2 | cut -d'|' -f2 | tr -d ' ')"
	for container_name in ${container_names}; do
		if [ "${delete}" -ne 0 ]; then
			"${0}" "${container_name}" --delete
			continue
		fi
		"${0}" "${container_name}"
	done
	exit
fi

# If we delete, just ask confirmation and exit.
if [ "${delete}" -ne 0 ]; then
	rm -f "${XDG_DATA_HOME:-${HOME}/.local/share}/applications/${container_name}.desktop"
	exit
fi

if ! command -v curl > /dev/null && ! command -v wget > /dev/null; then
	printf >&2 "Icon generation depends on either curl or wget\n"
	printf >&2 "Fallbacking to default icon.\n"
	download="null"
fi

if command -v curl > /dev/null 2>&1; then
	download="curl --connect-timeout 3 --retry 1 -sLo"
elif command -v wget > /dev/null 2>&1; then
	download="wget --timeout=3 --tries=1 -qO"
fi

# We depend on a container manager let's be sure we have it
# First we use podman, else docker, else lilipod
case "${container_manager}" in
	autodetect)
		if command -v podman > /dev/null; then
			container_manager="podman"
			container_manager_cp_command="podman cp"
		elif command -v podman-launcher > /dev/null; then
			container_manager="podman-launcher"
			container_manager_cp_command="podman-launcher cp"
		elif command -v docker > /dev/null; then
			container_manager="docker"
			container_manager_cp_command="docker cp -L"
		elif command -v lilipod > /dev/null; then
			container_manager="lilipod"
			container_manager_cp_command="lilipod cp"
		fi
		;;
	podman)
		container_manager="podman"
		container_manager_cp_command="podman cp"
		;;
	podman-launcher)
		container_manager="podman-launcher"
		container_manager_cp_command="podman-launcher cp"
		;;
	lilipod)
		container_manager="lilipod"
		container_manager_cp_command="lilipod cp"
		;;
	docker)
		container_manager="docker"
		container_manager_cp_command="docker cp -L"
		;;
	*)
		printf >&2 "Invalid input %s.\n" "${container_manager}"
		printf >&2 "The available choices are: 'autodetect', 'podman', 'docker', 'lilipod'\n"
		;;
esac

# Be sure we have a container manager to work with.
if ! command -v "${container_manager}" > /dev/null; then
	# Error: we need at least one between docker, podman or lilipod.
	printf >&2 "Missing dependency: we need a container manager.\n"
	printf >&2 "Please install one of podman,  docker or lilipod.\n"
	printf >&2 "You can follow the documentation on:\n"
	printf >&2 "\tman distrobox-compatibility\n"
	printf >&2 "or:\n"
	printf >&2 "\thttps://github.com/89luca89/distrobox/blob/main/docs/compatibility.md\n"
	exit 127
fi

# add verbose if -v is specified
if [ "${verbose}" -ne 0 ]; then
	container_manager="${container_manager} --log-level debug"
	container_manager_cp_command="${container_manager_cp_command} --log-level debug"
fi

# prepend sudo (or the specified sudo program) if we want our container manager to be rootful
if [ "${rootful}" -ne 0 ]; then
	extra_flags="${extra_flags} --root"
	container_manager="${distrobox_sudo_program:-"sudo"} ${container_manager}"
	container_manager_cp_command="${distrobox_sudo_program:-"sudo"} ${container_manager_cp_command}"
fi

if ! ${container_manager} inspect --type container "${container_name}" > /dev/null; then
	printf >&2 "Cannot find container %s. Please create it first.\n" "${container_name}"
	exit 1
fi

# Ensure the destination dir exists.
mkdir -p "${XDG_DATA_HOME:-${HOME}/.local/share}/applications"
mkdir -p "${XDG_DATA_HOME:-${HOME}/.local/share}/icons/distrobox"

distrobox_path="$(dirname "$(realpath "${0}")")"
entry_name="$(echo "${container_name}" | cut -c1 | tr "[:lower:]" "[:upper:]")$(echo "${container_name}" | cut -c2-)"

if [ "${icon}" = "auto" ]; then
	# Set icon to the generic terminal as a fallback.
	icon="${icon_default}"
	# This is a NON comprehensive list of logos of the most popular distributions. If you find logos for
	# other supported distros, add it here.
	DISTRO_ICON_MAP="
		alma:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/alma-distrobox.png
		alpine:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/alpine-distrobox.png
		arch:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/arch-distrobox.png
		centos:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/centos-distrobox.png
		clear--os:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/clear-distrobox.png
		debian:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/debian-distrobox.png
		deepin:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/deepin-distrobox.png
		fedora:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/fedora-distrobox.png
		gentoo:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/gentoo-distrobox.png
		kali:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/kali-distrobox.png
		kdeneon:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/kdeneon-distrobox.png
		opensuse-leap:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/opensuse-distrobox.png
		opensuse-tumbleweed:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/opensuse-distrobox.png
		rhel:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/redhat-distrobox.png
		rocky:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/rocky-distrobox.png
		ubuntu:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/ubuntu-distrobox.png
		vanilla:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/vanilla-distrobox.png
		void:https://raw.githubusercontent.com/89luca89/distrobox/main/docs/assets/png/distros/void-distrobox.png
	"
	# Try to detect container's distribution by using /etc/os-release
	${container_manager_cp_command} "${container_name}":/etc/os-release /tmp/"${container_name}".os-release
	container_distro="$(grep "^ID=" /tmp/"${container_name}".os-release |
		cut -d'=' -f2- |
		sed "s|linux||g" |
		tr -d ' ' |
		tr -d '"')"

	if [ "${rootful}" -ne 0 ]; then
		${distrobox_sudo_program:-"sudo"} rm -f /tmp/"${container_name}".os-release
	else
		rm -f /tmp/"${container_name}".os-release
	fi

	icon_url="$(echo "${DISTRO_ICON_MAP}" | grep "${container_distro}:" | cut -d':' -f2-)"

	# Distro not found in our map, fallback to generic icon
	if [ -z "${icon_url}" ]; then
		icon_url="https://raw.githubusercontent.com/89luca89/distrobox/main/icons/terminal-distrobox-icon.svg"
		container_distro="terminal-distrobox-icon"
	fi

	if [ -n "${icon_url}" ] && [ "${download}" != "null" ]; then
		icon_extension="${icon_url##*.}"

		if [ "${online}" -lt 1 ] && ${download} - "${icon_url}" > "${XDG_DATA_HOME:-${HOME}/.local/share}/icons/distrobox/${container_distro}.${icon_extension}"; then
			icon="${XDG_DATA_HOME:-${HOME}/.local/share}/icons/distrobox/${container_distro}.${icon_extension}"
		else
			# Wget failed for some reasons. Default to generic terminal icon as declared at the beginning.
			printf >&2 "Warning: Failed to download icon. Defaulting to generic one.\n"
		fi
	else
		# Distribution not found in the list. Default to generic terminal icon as declared at the beginning.
		printf >&2 "Warning: Distribution not found in default icon set. Defaulting to generic one.\n"
	fi
fi

cat << EOF > "${XDG_DATA_HOME:-${HOME}/.local/share}/applications/${container_name}.desktop"
[Desktop Entry]
Name=${entry_name}
GenericName=Terminal entering ${entry_name}
Comment=Terminal entering ${entry_name}
Categories=Distrobox;System;Utility
Exec=${distrobox_path}/distrobox enter ${extra_flags} ${container_name}
Icon=${icon}
Keywords=distrobox;
NoDisplay=false
Terminal=true
TryExec=${distrobox_path}/distrobox
Type=Application
Actions=Remove;

[Desktop Action Remove]
Name=Remove ${entry_name} from system
Exec=${distrobox_path}/distrobox rm ${extra_flags} ${container_name}
EOF
